1. Technical Field
The present invention relates to a sensing and warning device for a driveway; and more particularly, relates to a combination solar, and battery powered, electromagnetic driveway sensing and warning device that alerts the occupant inside the premises to the presence of driveway traffic via a radio signal that triggers an audio chime located within the premises, or for warning a driver of a vehicle about an overhanging object in the driveway.
2. Description of Related Art
A patentability search was conducted and many different patents were found.
U.S. Pat. No. 2,588,879 discloses an automatic garage door opening system that includes a loop of wire on a driveway or slightly buried in a position to inductively couple with an antenna loop in an automobile. The automatic garage door opener is actuated by sensors located on the driveway, so that when a car fitted with a complementary device pulls up to the garage door, the door automatically opens for only that particular car.
U.S. Pat. No. 4,232,285 discloses an electromagnetic detector designed to monitor vehicle road traffic, having a transmitting coil means and a receiving coil spaced therefrom over a metal base. When a vehicle passes over the metal base, a disturbance in an induced field is detected. In operation, the electromagnetic detector is located on a road responsive to a modification of a magnetic field in a system for the monitoring of road traffic.
U.S. Pat. Nos. 4,523,193 and 5,748,074 disclose remote controlled doorbell systems that include a radio signal transmitter coupled with a doorbell and a radio signal receiver that produces a signal to activate a tone generator. The remote controlled doorbell systems may have several receivers located throughout the residence.
U.S. Pat. No. 5,023,595 discloses a mail arrival system that uses a solar powered radio frequency transmitter attached to the mailbox and actuated by opening a mailbox door. Solar cells are shown on a transmitter housing. A receiver located in a residence produces an audible musical tune.
U.S. Pat. No. 5,604,478 discloses a pet operable door chime system that includes a switch unit with a radio frequency transmitter operated by a pet placing a paw on the upper surface, and a receiver designed to produce a chime when the radio signals are received.